A pivotal sash window adapted for installation in a master frame of a sash window assembly is well-known. The sash window assembly typically has opposed, vertically extending guide rails to enable vertical reciprocal sliding movement of the sash window in the master frame while cooperatively engaged with the guide rails. The sash window has a top sash rail, a base and a pair of stiles cooperatively connected together at adjacent extremities thereof to form a sash frame, usually a rectangular frame. Typically, a pair of spaced tilt-latches are installed on, or in, opposite ends of the top sash rail.
Each tilt-latch is generally comprised of a housing having an outward end opening and a latch bolt disposed within the housing. A spring disposed within the housing generally biases the latch bolt through the outward end opening to engage the guide rails of the master frame. The latch bolt has an actuator structure to allow for actuation of the latch bolt. The actuator structure is typically a small control button that is connected to the latch bolt. An operator can use his finger to engage the actuator wherein the latch bolt is retracted into the housing. This releases the latch bolt from the guide rail. When the latch bolts of the opposed tilt-latches are actuated simultaneously, the sash window can then be pivoted from the master frame.
A tilt-latch mounted in a top sash rail is typically called a flush-mount tilt-latch. Examples of this type of tilt-latch are shown in U.S. Pat. No. 5,139,291, and application Ser. No. 09/121,289, both assigned to Ashland Products, Inc., the assignee of the present invention, and incorporated by reference and made a part hereof. To accommodate the flush-mount tilt-latch in the top rail, a slot is punched or routed in the top rail.
Pivotal sash window assemblies can be constructed from different materials such as vinyl or wood materials. Tilt-latches and other window hardware components have often been made from plastic using injection molding technology. Such components have also been made from metal materials such as zinc. In a wood window application or simulated wood window application wherein the window assembly has a simulated wood appearance (e.g., wood-style laminate applied over a PVC extrusion), consumers have oftentimes preferred the aesthetic features of metal hardware over plastic hardware. A plastic tilt-latch is just not as aesthetically pleasing in a wood window as a metal tilt-latch. Thus, in wood windows, tilt-latches made from zinc are often used. Zinc tilt-latches, like other metal hardware, are typically more robust that traditional plastic tilt-latches, but also more expensive. In addition, due to the sliding interaction between the metal components of zinc tilt-latches upon actuation, unwanted noise is produced. As a result, consumers sometimes conclude that the zinc tilt-latches, when actuated, do not possess smooth operational characteristics. Expressed differently, the zinc tilt-latches, when actuated, may produce an unwanted metal-on-metal “ringing” sound. Consumers then may question the quality of the tilt-latches due to the unwanted noise produced during actuation. In addition, all zinc tilt-latches include a zinc latch bolt having a nose that is adapted to engage a respective one of the guide rails of the master frame. Because of the hardness of zinc, the latch bolt nose can sometimes damage wood or plastic guide rails when the sash window is pivoted to a closed position where the nose engages an outer portion of the guide rail and moves into the brake shoe channel.
The present invention is provided to solve these and other problems.